The goals of this proposed project are to determine: (1) the ability of the larvae and postlarvae of oysters to absorb and metabolize organic compounds such as amino acids and monosaccharides which have been shown to be dissolved in sea water; (2) the physiological mechanisms by which these compounds are absorbed; and, (3) the optimal environmental conditions (e.g. temperature, salinity, ion requirements) for the absorption and utilization of these nutrients.